Betta and Guppy Compatibility
Betta (Siamese Fighting Fish) and Guppy are not recommended: temperature ranges overlap at 76–82°F, and the behavioural or size conflict is not solved by adding space. Plan on at least 10 gallons. Individual fish vary — observe behaviour during introduction.
Betta vs Guppy at a glance
Why this verdict
- Temperature: Shared range of 76–82°F.
- Water parameters: Shared pH range of 6.8–7.5.
- Temperament: Betta (Siamese Fighting Fish) can be territorial; provide plants, sight breaks, and space.
- Adult size: Comparable adult sizes (~2.5" and ~1.8").
- Swimming zone: Both are top-dwelling, but peaceful — sharing the layer is fine with cover.
- Schooling: Group sizes matter: Guppy: keep at least 3.
- Tank size: Plan for at least 10 gallons to satisfy both species.
Main risks
- Occasional chasing or fin nipping is possible.
- Guppy fins look like competition to a betta; nipping and stress are common in both directions.
- Overlapping temperature ranges do not overcome the behavioral conflict.
Exceptions & caveats
Endler's livebearers (smaller, faster guppy relatives) sometimes work with docile bettas in heavily planted tanks.
Recommended tank
Plan on 10 gallons or larger for this pair. Suitable sizes: 10 gallon, 15 gallon, 20 gallon High.
Group sizes: Guppy: keep at least 3.
Sources
- FishBase — Scientific Database · Primary / scientific · https://www.fishbase.se/
- SeriouslyFish — Specialist Publication · High authority · https://www.seriouslyfish.com/
- Aquarium Forge editorial guidelines — Editorial Interpretation · Editorial interpretation
- FishBase — Scientific Database · Primary / scientific · https://www.fishbase.se/
- SeriouslyFish — Specialist Publication · High authority · https://www.seriouslyfish.com/
- Aquarium Forge editorial guidelines — Editorial Interpretation · Editorial interpretation
- Aquarium Forge editorial guidelines — Editorial Interpretation · Editorial interpretation
Compatibility verdicts are planning guidance, not guarantees — individual fish vary. Rule version 1.1 · Data reviewed: .
Frequently asked questions
Can Betta and Guppy live together?
Our verdict is “Not Recommended”. Betta (Siamese Fighting Fish) and Guppy are not recommended: temperature ranges overlap at 76–82°F, and the behavioural or size conflict is not solved by adding space. Plan on at least 10 gallons. Individual fish vary — observe behaviour during introduction.
What tank size do Betta and Guppy need?
Plan for at least 10 gallons so both species have their minimum space — Betta needs 5+ gal and Guppy needs 10+ gal. Adding length and cover reduces stress further.
What temperature do Betta and Guppy share?
Their comfortable ranges overlap at 76–82°F. Hold the tank near the middle of that band and avoid the extremes of either species' range.
What are the main risks keeping Betta with Guppy?
Occasional chasing or fin nipping is possible. Guppy fins look like competition to a betta; nipping and stress are common in both directions. Overlapping temperature ranges do not overcome the behavioral conflict.
How many Betta and Guppy should I keep?
Guppy: keep at least 3. Group sizes matter for shoaling fish — too few and they become stressed and nippy.
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